Valve



H. SLATER. VALVE.

APPLICATION FILED MAR. l5 |920.

1,378,141. y patented May17,11921.

H. SLATER.

VALVE.

APPLICATION FILED MAR. I5 |920.

Patented May 17, 1921 3 SHEETS--SHEET 3- III IIIIIIII' llulnum III .EMINEM ATTORNEYS.

UNITED `STATES PATENT OFFICE.

HARVEY SLATER, F CHICAGO, ILLINOIS, ASSIGNOR T0 CHARLES F. ELMES ENGI. NEERING WORKS, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS,

vAIlvE.

Specification of Letters Patent. Patented May 17, 1921.

Application filed March 15, 1929. Serial No. 365,703.

To all 'whom z't may concern Be it known that I, HARVEY SLATER, a citizen ofthe United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in' Valves, of which the following is a specification.

This invention relates to that general type of high pressure valves covered by my United States Letters Patent No. 1,143,236, and contemplates specifically a double valve composed of units such as disclosed in said patent coperatively associated for efficient and economical use in connection with a hydraulic press orother type of press operated by a fluid under high pressure.

In the operation of hydraulic presses which have a comparatively long working stroke and which requires a high pressure only near the end of said stroke, at which time the moving die is acting upon the material to be compressed, it has been found -advisable to employ both a low and a high ressure fluid. The reasony for this is that ittle compressive work is done untilnear the bottom of the working stroke, and if only high fessure uid is employed a great quantity t ereof is consumed in simply actuating the piston of the press without accomplishing the high compressive work for which it was intended. -This results in ineiciency,-a waste of high pressure Huid, since to build up and maintain such a high pressure requires, as is known, a considerable amount of power.v

It has become a practice, therefore, to employ, as stated above, both a high-pressure fluid and a low pressure fluid in the operation of such presses. The low pressure Huid, thepressure in which is comparatively proportion to' the amount of work turned out, there .is a tendency on the part of said operator, -1n order to hasten each press operatlon, elther to apply the high-pressure fluid too qulckly, or, in more flagrant cases, to make use of the high pressure fluid throughout lthe entire stroke, either of which abovementloned practices would result in ineiiiclent yand uneconomical use of pressure. l The present invention, therefore, has for its primary object the provision of coperat- 1ng high and low pressure valves which function to automatically introduce a highpressure fluid to the pressure cylinder only when the piston, actuated by the low pressure fluid, nears the lower part of its working stroke and actually commences its compressive work.

l Another object is to provide a valve which 1s simple in construction, which is foolproof, and which operates automatically to introduce high pressure Huid at the proper time, thus dispensing w-ith the services of an operator for this particular duty andv permitting one operator to attend several presses.

Further objectsand advantages of my invention will become evident from the following description and drawings based thereon.- Inasmuch as the principle cf the invention is capable of being applied in constructional forms other than the one illustrated, it is not intended that the scope of the appended claims should be unnecessarily limited thereby. f

In 'the drawings- Figure -1 is a top plan view of the double valve;

Fig. 2 is a side elevation of the same;

Fig. 3 is a central, longitudinal section on an enlarged scale;

Fig. 4 is an assembly view showing the pressure cylinder of a press operatively connected with the valve of the present dis.-

closure; and Fig..5 is a vertical transverse section on the line 5-5 of Fig. 2.

Having particular reference to the drawings the numeral 11 designates a casing, which contains two parallel andvlongitudinally disposed bores 12 in `which`are positioned twin valves, each of which is quite similar to the valve disclosed in my previously mentioned Letters -Patent No. 1,143,236. Inasmuch asthe twin valves are duplicates a, brief description of one will suffice for the other, the coeflicient a being used on 'the drawings to signify a corresponding part of the other valve.

One end of bore 12 is closed by a screw plug 13. Opening upon said ybore and displaced in order longitudinally in the casing 11 are a. pressure inlet 14, a machine supply port 15 and an exhaust port 16. The bore 12 of the casing between the inlet 14 and the port 15 contains a sleeve 17 lixedly disposed and held .against a shoulder in said bore by the above-mentioned screw plug 13. Packing is positioned between said sleeve and screw plug in order to prevent leakage of the pressure fluid. Sleeve 17 forms in bore 12 an apertured partition which functions as a guide and seat for the inlet controlling valve 18, the stem 19 of which is guided within a bore in the plug 13 and there engaged by a compression spring 20. Said spring acts to maintain the valve 18 in closed position against its seat in sleeve 17. Said sleeve is apertured as at 21, adjacent the pressure inlet 14 in order to permit an inflow of fluid to valve 18. Radial oblique ports 22 are ositioned in sleeve 17 below the seat of va ve 18 and function to allow the pressure fluid unobstructed pas' sage to the chamber 23- which opens on the machine supply port 15. That portion of valve 18 below its seat in sleeve 17 is contracted for a short portion of its length, below which contraction, it is radially 'flanged for guiding the valve in said sleeve. The flanged portion of valve 18 extends beyond sleeve 17 into chamber 23, as' shown in Fig. 3. A shoulder 24 is formed in bore l2 between the machine supply port 15 and the exhaust port 16. A guide sleeve 25 is fixedly disposed in this portion of the bore and bears upon packing positioned between said sleeve and shoulder. ed in the sleeve 25 and adapted to be brought into engagement with the pressure inlet valve 18-is a sliding piston 26 having a passage way 27 extending therethrough which functions to place the ymachine port 15 in fluid communlcation with the exhaust port 16. A bonnet 28 is threaded into the end of bore 12 opposite the screw plug 13. The inner end of said bonnet provides a stop for limiting the movement of piston 26 in that direction. The bonnet contains a lon- 'tudinal bore, which bore at its inner end 1s enlarged to form a chamber 29. Said chamber is open to exhaust port 16 which is disposed between the bores 12 and common to each of the twin valves, the communication between said chamber and port being accomplished by apertures 30 in the sidewalls 'of the bonnet.

Extending through the bore in bomlet 28, and guided thereby is the stem of-an exhaust controlling. valve 31, the head of which seats in the passage-way 27 of pis- Slidably mountton 26 thus closing fluid communication through said passage way. The length of piston 26 is so proportioned that the inlet valve 18, which is opened by the pressing contact of the end of said piston, may move into closed position before the piston is stopped against bonnet 28.

The foregoing description explains the construction of the two valves, positioned in bores 12, which valves, as before stated, are duplicates. The exhaust port 16 therebetween is open to both valves andfunctions as a common outlet.

A bore 32 is positioned in casing 11 between the bores 12 and has its axis perpendicular to the piane of the axes of bores 12, 12a, as shown in the drawings. A sleeve 33 is fixedly positioned in bore 32 and contains a small axial bore 34. This partitionlike'sleeve forms the bore 32 into an upper and ra lower chamber, 35 and 36 respectively. Said bore intersects lbore 12, thus putting chamber 35 of bore 32 into open communication with chamber 23 of bore 12, as shown in Figs. 3 and 5.

An oblique port 37 through the casing connects chamber 36 with the inlet 14a.

A pressure valve 38 is guided. in a bonnet 39 screwed into the top of bore 32. Said valve seats upon the topof the small bore in sleeve 33 where it is held by the compression of a spring 40 located in said'bonnet between the enlarged portion of the valve and a compression adjusting bonnet 41. That part of valve 38 which is exposed in chamber 35 contains a pressure surface or shoulder 42. A screw plug 43 effectively closes the bottom of bore 32.

A cross-head 44 is rigidly disposed at one end of casin 11 by means of the anchoring bolts 45. Said cross-head contains two bores within which are threaded screw spindles 46, 46 longitudinally alined with the valve stems 31, and 31a. Intermeshing gear wheels 47, 47, are keyed to the 'screw spindles. An operating handle 48 is also keyed .to spindle 46so that when, by means of handle 48, one spindle is rotated and moved inward the other will automatically move outward, and vice versa.

A housing 49 covers the gear wheels 47, 47 a and forms aprotection 'for t-he same.

The operation of this device is as follows: y means of suitable connecting pipes inlet 14 is connected to a low-pressure fluid supply with lan interposed non-return check valve 50, port 15 to that end of a hydraulic press cylinder above the piston head, exhaust port 16 back to the fluid reservoir; inlet 14EL to a high pressure fluid supply and port 15a to that end of the hydraulic press cylinder space below the head of the piston,

and only a small area of the piston shoulder is exposed in the cylinder to the liquid, it is desirable to use high pressure fluid on the return stroke, since a comparatively high pressure is needed, and only a small quantity thereof is consumed in this operation.

Assume for the purposes of exempliiication that the pressure at the low` pressure inlet 14 is 200 pounds, and at the high pressure inlet 14, 1,000 pounds. As shown in Fig. 3 the valves in this device are closed. In order to operate the press, the screw spindle is moved inwardly by rotation of handle 48 in a clock-wise direction. Said spindle impinges against the stem of valve 31, said valve, which is seated against the piston 26, actuates the piston and said piston unseats valve 18, permitting the low pressure Huid to flow into chamber 23 and through the. port 15 into that part of the hydraulic press cylinder above the piston.

At the same time the screw spindle 46 being actuated, because of the gear wheels 47, 47 in a direction opposite to that of spindle 46 allows the valve 31 to unseat from piston 26 and permits the fluid below the piston in the hydraulic cylinder to pass from port 15 into the exhaust port 16, thevalve 18 meanwhile remaining closed.

Slnce port 37 is always in open communication with the high pressure inlet 14 valve 38 (Fig. 5) is adjusted byl means of the bonnet 41 acting on spring 40 to prevent the unseating of said valve by the high pressure fluid acting on the small area of the lower reduced end thereof from chamber 36. However, when the pressure in chamber 35, which is equivalent to that pressure above the piston in the hydraulic cylinder, rises to near its maximum (in this 'case 200 pounds) due to the retarding of the piston upon coming in contact with the material,

to be compressed, this added pressure of approximately 200 pounds acting on the larger area of the shoulder 42 of valve.) 38 is suiiicient when coperating with the high pressure below said valve to compress spring 40 and raise the valve from its seat.

As said valve thus opens fluid communication `between the high pressure fluidinlet 14 and the machine supply port 15, the high pressure fluid is introduced into the cylinder and acts upon the piston, at high pressure in lieu of the previous low pressure. Thus the high pressure fluid is applied to the piston during that portion only of its stroke-when high pressure is required to perform the work. The previously mentioned check Valve 50, disposed in the connecting pipe leading to the low pressure supply port 14, prevents a back flow therethrough.

When it is desired that the pressure behind the piston be released and the piston be returned to its initial position, the handle 48 being no longer held open against the compression of spring 20, is seated and closes communication with the inlet supply port 14. Valve 31 is unseated from piston 26 due to the pressure built up in chamber 23 and passage 27, thus permitting the discharge of fluid from the machine supply port to the exhaust port 16. As soon as the pressure in the machine supply port 15 has dropped sufliciently, the pressure actuated valve 38 in bore 32 automatically closes.

At the same time, due to the'movement of spindle 46, valve 31, and piston 26, valve 18 is unseated and valve 31 seated and Securely held against its seat in piston 26, permitting high pressure Huid from inlet 14 to flow past valve 18 into machine supply port 15 and clos-ing off Huid communication between said machine support port and exhaust nomically utilize low pressure fluid during the greater portion of the working stroke of a press, drawing upon the high pressure supply only as and when high compresisve work is required of the press, and quickly returning the press platen at the end of its work stroke by the comparatively small expenditure of high pressure fluid; all with automatic certainty and precision.

I claim:

1. In a device of the character described, the combination of two valve mechanisms each including an inlet, an exhaust and a machine-supply port, means in each of said mechanisms whereby its machine-supply port is put in alternate' communication first with its inlet and then with its exhaust, means for operating both valve mechanisms in s vnchronism whereby when communication between the machine-supply port and inlet of one isopened communication between the Inachine-supply port and exhaust of the other is iuid and the other to a source of high pressure Huid, means in each of said mechanisms whereby its machine-supply port is put in alternate communication first with its inlet and then with its exhaust, means for operating both-valve mechanisms in synchronism whereby when communication between the machine-supply port and inlet of one is opened communication between the machine-supply port and exhaust of the other is opened, and vice versa, and means to establish communication between the high pressure inlet of one valve mechanism and the machine-supply port of the other whereby when the pressure in the latter port reaches a predetermined amount communication will automatically open therebetween.

3. In a device of the character described, the combination of two valve mechanisms each including an inlet, an exhaust and a machine-supply port, the inlets connected respectively one to a source of low pressure Huid and the other to a source of high pressure fluid, a non-return check valve positioned in the connection leading to the low pressure fluid inlet, means in each of said mechanisms whereby its machine-supply port is put in alternate communication first with its inlet and then with its exhaust, means for operating both valve mechanisms in synchronism whereby when communication between the machine-supply port and inlet of one is opened communication between the machine-supply port and exhaust of the other is opened, and vice versa, means to establish communication between the high pressure inlet of one valve mechanism and the machine-supply port of thevother whereby when the pressure in the latter port reaches a predetermined amount'communication will automatically open therebetween.

4. In a device of the character described, the combination of two valve mechanisms each including an inlet, an exhaust and a machine-supply port, means in each of said,-

mechanisms whereby its machine-supply port is put in alternate communication first with its inletl and then with its exhaust, said means comprising in each mechanism a normally closed inlet valve disposed between the inlet and the machine-supply port and an exhaust valve between the machine-supply port and exhaust, the valves'being cooperatively positioned whereby the vinlet valve is caused to open or close by the respective closing or opening of the exhaust valve, means for operating both valve mechanisms in synchronism whereby when communication between the machine-supply port and inlet of one is opened-communication between the machine-supply port and exhaust of the other is opened, and vice versa, and means toestablish communication between the inlet of one valve mechanism and the machine-supply port of the other whereby when the pressure in the latter port reaches a predetermined amount communication4 will automatically open therebetween.

5. In a device of the character described, the combination of two valve mechanisms each including an inlet, an exhaust and a machine-supply port, means in each of said mechanisms whereby its machine-supply port is put in alternate communication first with its inlet and then with its exhaust, means for operating both valve mechanisms in synchronism whereby when communication between the machine-supply port and inlet of one is openedcommunication between the machine-supply port and exhaust of the other is opened, and vice versa, said means comprising two screw spindles alined in operative Contact with the stems of said exhaust valves, intermeshing gears keyed on said spindles, means provided on one of said spindles for rotating the same, and means to establish communication between the inlet of one valve mechanism and the machine-supply port of the other whereby when the pressure in the latter port reaches a predetermined amount communication will automatically open therebetween.

6. In a device of the character described, the |combination of two Valve mechanisms each including an inlet, an exhaust and a machine-supply port, means in each of said mechanisms whereby its machine-supply port is put in alternate communication lirst with its inlet` and then with its exhaust, means for operating both valve mechanisms in synchronlsm whereby when communication between the machine-supply port and inlet of one is opened communication between the machine-supply port and exhaust of the other is opened, and vice versa, and means to establish communication between the inlet of one valve mechanism and the machine-supply port of the other whereby when the pressure in the latter port reaches a predetermined amount communication will automatically open therebetween, said last mentioned means comprising a passage therebetween, a pressure actuated valve disposed in the passage, said valve presenting an effective pressure surface to the inlet and another effective surface to the port, and a compression spring normally holding said of the other is opened, and vice versa, and means to establish communication between the inlet of one valve mechanism and the machine-supply port of the other whereby when the pressure in the latter port reaches a predetermined amount communication will automatically open therebetween, said last mentioned means comprising a passage therebtween, an inwardly opening pressure-actuated valve disposed in the passage, said valve presenting an effective pressure surface to the inlet and another effective pressure surface to the port, and a compression spring normally holding said valve closed against its seat, and means for adjustingsaid spring to determine the combined pressure acting on the valve at which the valve will open.

8. In a device of the character described, the combination of two valve mechanisms each including an inlet, an exhaustand a machine-supply port, the inlets connected respectively one to a source of low pressure fluid and the other to a source of high pressure fluid, a non-return check valve positioned in the connection leading to the low pressure fluid inlet, means in each of said mechanisms whereby its machine-supply port is put in alternate communication first with its inlet and then with its exhaust, said means comprising in each mechanism a normally closed inlet valve disposed between the inlet and the machine-supply port and an exhaust valve between the machine-supply port and exhaust, the valves being cooperatively positioned whereby the inlet valve is caused to open or close by therespective closing or opening of the exhaust valve, means for operating both valve mechanisms in synchronism whereby when communication between the machine-supply port and inlet of one is opened communication between the machine-supply port and exhaust of the other is' opened, and vice versa, said means comprising two screw spindles alined in operative contact with the stems of said exhaust valves,` intermeshing gears keyed on said spindles, means provided on one of said spindles for rotating the same, and means to establish communication between the high pressure inlet of one valve mechanism and the machine-supply port of the other whereby when the pressure in the latter port reaches a predetermined amount communication will automatically open therebetween, said last mentioned means comprising a passage therebetween an inwardly opening pressure-actuate valve disposed in the passage, said valve presenting an effective pressure surface to the inlet and another effective pressure surlface to the port, and a compression spring normally holding said .valve closed against its seat, and means for adjusting said spring to determine the combined pressure acting on the valve at which the valve will open.

In testimony whereof I have hereunto signed my name in the presence of two subscribing witnesses.

HARVEY SLATER.

Witnesses F. O. SMITH, HAROLD GEE. 

